Reading that I thought that there would be more shoreline than that on the Greatlakes including the islands because of the immensity of it all but I guess its probably as accurate as it can me.
https://en.wikipedia.org/wiki/Great_Lakes
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The Great Lakes contain
21% of the world's surface fresh water: 5,472 cubic miles (22,810 km3), or 6.0×1015 U.S. gallons, that is 6 quadrillion U.S gallons, (2.3×1016 liters).
This is enough water to cover the 48 contiguous U.S. states to a uniform depth of 9.5 feet (2.9 m). Although the lakes contain a large percentage of the world's fresh water, the Great Lakes supply only a small portion of U.S. drinking water on a national basis.
The total surface area of the lakes is approximately 94,250 square miles (244,100 km2)—nearly the same size as the United Kingdom, and larger than the U.S. states of New York, New Jersey, Connecticut, Rhode Island, Massachusetts, Vermont, and New Hampshire combined.
The Great Lakes coast measures approximately 10,500 miles (16,900 km);
however, the length of a coastline is impossible to measure exactly and is not a well-defined measure (see Coastline paradox). Of the total 10,500 miles (16,900 km) of shoreline, Canada borders approximately 5,200 miles (8,400 km), while the remaining 5,300 miles (8,500 km) are bordered by the United States. Michigan has the longest shoreline of the United States, bordering roughly 3,288 miles (5,292 km) of shoreline, ...
Traversing the shoreline of all the lakes would cover a distance roughly equivalent to travelling half-way around the world at the equator.
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